Electric signal for telephone-lines



UNITED STATES PATENT @FFICP.

LE ROY swarms, or WATERBURY, oonnnorrour.

ELECTRIC 'SIG NAL FO R TELEPHONE-LINES.

SPECIFICATION forming'part of Letters Patent No. 236,131, dated December28, 1880.

Application filed Jul 2,1880. (ModeL) To all whom it may concern:

Be it known that "I, LE ROY S. WHITE, of Waterbury, in the county ofNew-Haven and State of Connecticut, have invented certain new and usefulImprovements in Electric Calls or Signals, of which the following is aspecification.

Although my improvements may be embodied in electric calls for variouspurposes, they are particularly adaptedfor use in connection withtelephone-lines to permit anyone instrument of a number of instrumentslocated upon one line to be calledfrom the central office withoutcalling all the instruments.

In carrying'outmy invention I use at the central office two batteriesofunequal strength or a battery comprising two portions, one of which maybe used separately, or both of which may be used combined; or I may use.other means of producing weak and strong currents. These batteries, ortheir equivalents, are connected with a line passing through the severalstations, and at each station is a branch cir cuit containing a bell.

My invention consists in the combination, in an electric call apparatus,of an electro-magnet, an armature therefor, means for: producing weakerand stronger currents of electricity in said magnet, a yieldingarmature-stop capable of resistingthe action of theweakercurrent butincapable of resistingthe action of the stronger one, a barrel which, inoperation, moves in one direction only, and is furnished with a ratchethaving one or more of its teeth longer or of greater pitch than theothers, and with one or more notches independent of said ratchetteeth, apawl connected to and moved by said armature to operate on said ratchet,and a projection, also connected with said armatureto enter said notchor notches.

The notch or notches in the barrels of the instruments at the severalstations are differently arranged relatively to the long tooth in theratchet, the notch in the barrel at one station being arranged one toothbehind the said long tooth, the notch in the barrel at anotherstation'being arranged two teeth behind said long tooth, and so on, thenumber of successive short teeth in the ratchet being in all cases atleast equal to the number of stations on theline. The yieldingarmature-stop, when it is pushed inward by the movement of the armatureunder a strong current, will close the branch circuit and sound the bellat any one station, provided that thenotch in the barrel at such stationis in such position that the projection upon the armature may enter itand thus perwit the full movementof the armature.

Inthe operation of my call a succession of weak currents, one more innumber thanthe successive short teeth of the ratchets, are sent throughthe line, and as the yielding armaturestopwill not permit the pawl tomove the ratchet forward the length of the long tooth, the long-teethratchets of the several barrels will, all be" brought to a positioncoincident with eachother. The position of the notch in the barrel ateach station relatively to the long ratchet-tooth being known, it isonly necessary, in making a call, to send a number of weak currentsthrough the line to bring the notch in the barrel at the station whichit is desired to call up to the projection, and then send a strongcurrent through the line,whereupon the projection at the desired stationwill enter the notch in the barrel, completing its full movement, andclose the bell-circuit,while the projections at all the other stationswill strike upon the periphery of the barrel, and thus prevent thearmatures from moving far enough to close the other branch circuits.

In the accompanying drawings, Figure 1 represents a vertical sectionthrough an apparatus embodying my invention, and a diagram view of thecircuits, batteries, and keys necessary to produce strong and weakcurrents. Fig. 2 represents a plan, partly in section, of the apparatus.Fig. 3 represents a sectional side view', on a larger scale, of aportion of the anmature and appurtenances, show- I ing more clearly themanner of closing the branch bell-circuit; and Fig. 4 represents aperspective view of the barrel, the upper portion of the armature, andthe pawl and projection, upon the same scale as Fig. 3.

Similar letters of reference designate corresponding parts in all thefigures.

A designates an ordinary electro-magnet, (shown as comprising twohelices,) and B designates an armature operated thereby in the usualway.

O designates a second electro-magnet, and

D the armature operated thereby for sounding the bell G by the hammer CWhen the branch circuit in which the said magnet is situated is closed.

The armature B is provided with an upwardlyprojecting arm, B, to theupper end of which is pivoted a pawl, I), and which is also providedwith a projection, e.

E designates a barrel adapted to turn in bearings at each end, whichexert a slight frictional resistance to the too free turning thereof.

I do not here claim the advancing step by step of the ratchet-wheel bythe armature under the impulse of a succession of weak currents ofelectricity; nor do I claim the armature adapted to move farther underthe impulse of a strong current to effect the closing of a localcircuit, as the same is fully described in my pending application, filedMay 19, 1880.

If desirable, a spring acting as a frictionbrake might be employed toprevent the barrel from turning backward. Near one end of this barrelare a series of ratchet-teeth, one or two of which, (1, are of greaterlength than the others, (I. The longer teeth d should, however, besituated, as here shown, at opposite sides of the barrel, so as to leavea succession of shorter teeth, one more, at least, in number than thenumber of stationsin the linecircuitbetween the longer teeth, for apurpose hereinafter described. The pawl b engages with theseratchet-teeth, as shown clearly in Fig. 4, and by the vibrations of thearmature B turns the barrel E.

The barrel E is provided in its periphery with a notch, 0, (see Fig. 4,)ot'a size to receive the point otthe projection c, and, as here shown,formed in a collar upon the barrel. The barrel may be conveniently madeof a single piece of iron or steel, with the notched collar andratchet-teeth formed in the same piece therewith.

The notches c in the barrels of the instruments at the several stationseach bear a (lifferent relation to the longer tooth d of the barrel, forapurpose hereinafter to be described. As shown clearly in Fig. 4, thenotch e is situated one tooth behind the longer tooth d. This barrelwould be the barrel of the instrument at station No. 1, while the notchat station No. 2 would be situated two teeth behind the longer tooth, atstation No. 3 three teeth behind the longer tooth, and so on with allthe stations.

F designates a yielding armature-stop, secured to the bed A andinsulated therefrom atf. The tension of the yielding stop F may beadjusted by means of a screw, a, of insulating material, having abearingin the armature-support.

Thearm B, attached to the armature, carries an adjustable screw, g, ofnon-conducting material, such as rubber, which strikes against the stopF when the armature is moved up by a current passed through the magnetA.When a weak current is passed through the magnet the strength of thestop is sufficient to stop the movement of the armature; but when astronger currentis passed through the magnet A the stop, being incapableof resisting the movement of the armature, is forced inward until theprojection 0 strikes upon the periphery of the barrel E. If, however,the pawl I) has moved the barrel sufficiently to bring the notch copposite the projection 0, the dent enters the notch and permits thestop to be forced in by the movement of the armature, acting through thescrew 9, until contact is made between the said stop and a contactpoint,h, embedded in insulating material, as shown clearly in Fig. 3, andconnected electrically with the magnet O in the branch bellcircuit, thusclosing the said branch circuit and ringing the bell.

The arrangement of the conductors and means for producing weaker andstronger currents of electricity will now be described.

Any means for producing weaker and stronger currents may be employed.The means here shown consists of a battery composed of two portions, HH, each of which are connected by conductors i t" with two keys, I 1.These keys are both connected by conductors j j with the main-line wireJ. By operating the key I the current is only derived from the portion Hof the battery and sent to the main conductor J by the conductor j.When, however, the key I is operated astronger current, derived fromboth portions of the battery, is sent through the conductor j to themain conductor J. From the binding-post K the current passes through themain conductor J to the magnets A, which are connected as shown in Fig.2, and thence through the conductor J back to the binding-post K and tothe portion H of the battery.

The branch bell-circuit is composed of a conductor, k, through which thecurrent passes from the binding-post K up through the column 0supporting the magnet O, and to said magnet; thence through the magnet,through the conductor 1, to the contact-point It. When the yielding stopF is pressed inward sufficiently to make contact with the point It thecircuit is closed, the current passing through the stop, thence througha conductor, m, back to the binding-post K, producing the ringing orstriking of the bell.

One advantage of my apparatus is that a simple vibrating bell may beused as only one station is called, instead of a stroke-bell.

It being understood that the notches e in the barrels of the severalinstruments are coincident severally with successive short teeth d ofthe ratchets upon the barrels, the operation is as follows: When theinstrument at any particular station is to be called a succession ofweaker currents, one more in number than the number of successive shortteeth in the ratchets, are sent through the line-wire, and by this meansthe barrels are all brought into a cointhrough the wire.

cident position, the several pawls I) being 0pposite the long teethd insaid barrels, and a single strong current is then given to cause thepawls b to pass the long teeth and start all the ratchetssimultaneously. If it is desired to call station N o. 1, a second strongcurrent is passed through the line-wire, and as the notch e in thebarrel at said station is now opposite the projection cthe projectionenters said notch and permits the armature to move inward, overcomingthe resistance offered by the stop, and pressing the latter against thecontact-point it, thus closing the branch bellcircuit and sounding thebell at station No. 1. At no other station, however, is the notch eopposite the projection 0, and therefore in all the other instrumentsthe dents strike against the peripheries of the barrels and block theinstruments. If it is desired to call station No. 2,a weak and a strongcurrent are sent If No. 3, two weak and one strong current. If No. 4,three weak and one strong current, and so on with all the stations.

It will be observed that the parts of my instrument which are new aresimple in c011- struction and few in number, and that therefore I amenabled to produce at a small cost a simple and durable instrument,which will not be liable to get out of order.

What I claim as my invention, and desire to secure by Letters Patent, is

1. The combination, in an electric call apparatus, of an electro-magnet,an armature therefor, means for producing weaker and stronger currentsof electricity in said magnet, a yielding armature-stop capable ofresisting the action of the weaker current but incapable of resistingthe stronger one, a barrel which is furnished with a ratchet having one.or more of its teeth longer or of greater pitch than the others and withone or more notches independent of said ratchet-teeth, a pawl connectedwith and moved by said armature to operate on the said ratchet, and aprojection also connected with said armature to enter said notch ornotches, all substantially as herein described.

2. The combination, with the electro-magnet and its armature and thepawl and projection attached to said armature, of the barrel constructedor furnished with a ratchet which extends entirely around it and which"has one or more of its teeth longer or of greater pitch than theothers, and constructed or fornished with a notched collar, the saidratchetteeth and notches occupying a fixed position relatively to eachother, substantially as herein described.

LE ROY S. WHITE. Witnesses:

FREDK. HAYNES, A. G. WEBB.

